Unitized radial shaft seals



June 2, 1964 B. H. CARSON ETAL 3,135,518

UNITIZED RADIAL SHAFT SEALs Original Filed Oct. 23, 1961 45 33 34 36 I846 le l5 United States Patent O UNTZED RADIAL SHAFT SEALS Brian H.Carson, Woodside, and John G. Barr, Redwood lCrty, Calif., assignors toFederal-Mogul-Bower Bearlugs, Inc., Detroit, Mich., a corporation ofMichigan Continuation of application Ser. No. 146,782, Oct. 23, 1961.This application Apr. 23, 1962, Ser. No. 189,525

18 Claims. (Cl. 277-37) This invention relates to improvements inunitized radial shaft seals. This application is a continuation ofapplication Serial No. 146,782 tiled October 23, 1961, now abandoned.

Patent 3,021,161 discloses a particularly good unitized shaft seal, andthe present invention relates to improvements upon some forms of theinvention covered by that patent. In a unitized shaft seal a wear sleeveis provided as part of an assembly to provide a manufacturer-suppliedsurface for the sealing lip to ride upon. The invention of Patent3,021,161 was characterized by having a wear sleeve made in two pieces,one of which is in contact with the shaft while the other is in contactwith the sealing lip of the radial sealing member and is also in contactwith the first-mentioned piece. The seal can be used in environmentshaving relatively high speed, where heretofore the heat generated by thefriction of the lipon the wear sleeve tended to cause trouble. The sealof Patent 3,021,- 161 dissipates the heat by providing an oil-slingingllange on the wear sleeve; lubricant hitting the llange is very rapidlyaccelerated and leaves the slinger tangentially at speeds greatly inexcess of the surface speeds obtained between the rotating shaft and anyoil which may be in contact with the shaft. Since the eiliciency andrate of heat transfer between a lluid and a solid is proportional to thesquare of the velocity between the two, the ilingng provides a veryhelpful cooling action.

ln some forms of this invention difficulties were experienced inspinning over a metal portion of the shaftcontacting wear sleeve pieceto which a rubber liner had been bonded in order to provide the shaftwith an elastomeric push-lit to the seal. Spinning was the most naturalWay of completing unitization of the two wear sleeve components to eachother and, in some constructions, was the main operation of uniting theentire assembly.V However, it became necessary in many instances toremove tightly bonded rubber flash from the portion of the metal casethat Was to be spun over; otherwise, the spinning operation becameimpractical. This removal was time-consuming and increased the cost ofthe seal.

An important object of the present invention is to solve this problem ofunitizing the wear sleeve and seal. It does this by providing a seal ofthe type of Patent 3,021,- 161 in which the secondary closing andspinning operations are eliminated, and a simple push-lit ofthelip-contacting wear sleeve past a rubber retaining member unitizes theseal. Moreover, by this means it becomes possible to have a quite looseassembly between the lip-contacting wear sleeve member and the memberhaving the rubber liner, for when the shaft is inserted through the sealthe rubber liner is then compressed under that Wear sleeve member andcauses it to be gripped tightly and therefore to be driven at the samespeed as the shaft.

The present invention has an additional advantage in that the rubbersleeve may be extended further than is actually required to retain thesleeve and provided with specially shaped protrusionsfor sealing akeyway in the shaft on which the seal rides. Such a keyway maycompletely pass underneath the seal and would otherwise provide a pathfor the oil to leak out in spite of the seal Vassembly. n

Other objects and advantages of the invention will appear from thefollowing description of some preferred forms thereof.

In the drawings:

FIG. l is a view in perspective of a unitized seal embodying theprinciples of the invention.

FIG. 2 is an enlarged fragmentary View in elevation and in section ofthe seal of FIG. l, taken along the line 2-2 in FIG. 1.

FIG. 3 is a view like FIG. 2 with the metal wear ring removed.

FIG. 4 is a fragmentary view in elevation and in section of aninstallation incorporating the seal of FIG. 1.

FIG. 5 is a fragmentary view in perspective and in section of a modiedform of a unitized seal also embodying the invention.

FIGS. 1 to 4 show a unitized seal 10 having a wear sleeve assembly 11and a sealing assembly 12. The wear sleeve assembly 11 includes twonested flanged annular rings 13 and 14. The ring 13 is all metal and isprovided with a cylindrical wear sleeve portion 15 having a radiallyouter sealing surface 16 and an opposite radially inner surface 17. Aradial oil-flinging flange 18- extends from one end of the cylindricalportion 15, giving the ring 13 a general L-shape as seen incross-section. Preferably, the ring 13 is formed by drawing a llatannular steel ring. The drawing is done by exertion of force on theradially inner surface 17 so that any scratches which may be produced onthat side do not affect the sealing surface 16. Minor undulations on thesealing surface 16 are insignificant and do not contribute to wear ofthe sealing lip. Thus, a smooth sealing surface is provided without anynecessity whatever for grinding.

The seal 10 is generally similar to the seal shown in FIG. 6 of Patent3,021,161 but has some important differences residing principally in thestructure of the ring 14 and with resulting differences in the assemblyof the seal 10. In the present invention the ring 14 comprises a metalmember 20 and a rubber member 21 bonded to the rnetal member 2li. Themetal member 20 is a ring generally L-shaped in cross-section having aradial flange 22 extending out from one end of a short axially extendingportion 23. The axially extending portion 23 is` quite short, muchshorter than the cylindrical portion 15 of the ring 13. As in Patent3,021,161 there is a rubber lining on the inner ring, but in the presentinvention the rubber lining 21 covers both sides of the portion 23 andextends a considerable distance beyond the end 24 of the portion 23providing the major length of the rubber-metal assembly 14, and it hasalip 25 at its outer end which provides the interlock connecting the ring14 to the ring 13, thereby eliminating any spinning of metal. As it fitsaround the base of the flange 18, the lip 25 locks the two portions 13and 14 of the wear sleeve 11 together, but the inner wear sleeve ring 13is removable. This, of course, has advantages in that the lip 25 can besnapped down and the wear sleeve ring 13 removed and studied. 1t caneven be replaced by a different ring 13, although that will rarely bethe case in actual installation.

At its other end the rubber member 21 extends on at least one side ofthe radial flange 22 where it provides a type of bumper portion 26 thataids in providing a labyrinthine-type of sealing arrangement whichprevents ingress of dirt from outside the oil seal 10.

The shaft seal assembly 12 may be any suitable type of shaft seal, theone shown being made by the method of Patent 3,004,298, having a case 30with a cylindrical portion 31, a radial flange 32, and a bent-interminal portion 33 to which is bonded an elastomeric sealing member 34having a sealing lip 35 in engagement with the sealing surface 16. Inthe form shown, a spring 36 assures contact of the lip 35 with thesurface 16, but a spring is not D always needed and its inclusion oromission does not affect the present invention.

Irl the form of the invention shown in FIGS. 1 3, there is also an outercase member 4@ having a cylindrical portion 41 with one end 42v spunaround the free end of the cylindrical case portion 31.l At the otherend of the cylindrical portion 41, there is a radially in-turned portion43 with a gasket 44 preferably between this portion 43 and the radialflange 32. There is also an offset portion l5 which lies radially outbeyond the inturned terminal portion 33 and connects to a second radialportion 46 of the outer case titl. This structure gives a space inbetween the radial portion 46 and the radial flange 32, and the radialflange 22 of the ring 14 extends up into this space unitizing the ring14 with the seal assembly 12, and therefore when the elastomeric lip issnapped around the base of the flange 18, the entire seal is unitized.There may be a rather loose fit until the apparatus is installed on theshaft (FIG. 4) inside the bore, at which time the expansion of therubber member 21 against the wear sleeve 13 acts to hold the wear sleeve13 quite snugly. The seal flange 32 and the flange 46 of the case 4)limit the flange 22 and hence the assembly 11 within a short range ofback-and-forth movement.

FIG. 5 shows a seal 50 identical to the seal 16 except for the provisionof a keyway filling projection 51 on its inner liner 52. Thisillustrates how it is possible to malte a unitized seal according tothis invention that will lit the keyway of the shaft on which it is tobe installed. The

precise shape depends on that of the keyway, just as its presence orabsence depends on whether the seal is to be located at or near such akeyway.

To those skilled in the art to which this invention relates, manyadditional changes in construction and widely differing embodiments ofthe invention will suggest themselves without departing from the spiritand scope of the invention as defined in the claims.

What is claimed is:

l. An annular unitized assembly for preventing lubricant loss betweentwo relatively rotatable machine members comprising: a seal assemblyhaving an annular case with a radial flange and an annular resilientmember having a sealing lip; an outer annular case locked to said sealassembly and adapted to have a stationary leak-tight fit with one saidmachine member and having an annular radial flange surrounding thesecond said machine member and stepped to provide a radially outerportion abutting the radial flange of said seal assembly case and anaxially outstepped radially inner portion spaced away therefrom; a metalring providing a generally cylindrical wear sleeve engaged by saidsealing lip; and a mounting and locking ring having a cylindricalelastomeric portion having a stationary leak-tight fit against saidsecond said machine member and fitting flush against the inner p ripheryof said wear sleeve for most of its axial extent and having a rubber lipat one end adapted to engage one axial extremity of said Wear sleeve anda metal member bonded to and supporting the other end of saidelastomeric portion and having a radial portion lying between saidradial flange of said seal assembly and said outstepped inner radialportion of said outer case so as to lock said mounting and locking ringto said cases.

2. The device of claim l wherein said radial flange of said mounting andlocking ring has an elastomeric facing bonded thereto.

3. The device of claim 1 having a gasket between the outer portion ofthe radial flange of said outer case and the radial flange of said sealassembly case.

4. A unitized seal, including in combination: an annular seal assemblyhaving a radial-type sealing lip; a generally cylindrical metal wearsleeve engaged by said sealing lip; a mounting and locking ring having acylindrical elastomeric portion lying flush against the inner peripheryof said wear sleeve for most of its axial extent and having i lockingmeans at one end adapted to hold one end of said wear sleeve, and ametal member bonded to and supporting the other end of said elastomericportion; and means to lock said seal assembly to said mounting andlocking ring so that the entire assembly is unitized upon installationof said wear sleeve.

5. In a plural-part annular unitized assembly for preventing lubricantloss between two relatively rotatable machine members, the combinationof: a seal assembly having an inner annular case with a cylindricalportion and a radial flange at one end thereof and an annular resilientlip member secured to said inner case and having a sealing lip; an outerannular case locked to said seal assembly, with a cylindrical portionenveloping the cylindrical portion of said seal assembly case andadapted to have a stationary leak-tight fit with one said machine memberand having an annular radial flange surrounding the second said machinemember and stepped to provide a radially outer portion abutting theradial flange of said seal assembly case and an axially outsteppedradially inner portion spaced away from the radial flange of said sealassembly case; a metal ring providing a generally cylindrical wearsleeve engaged by said sealing lip; and a mounting and locking ringhaving a cylindrical elastomeric portion adapted to have a stationary,leak-tight fit with said second machine member and fitting flush againstthe inner periphery of said wear sleeve for most of its axial extent andhaving a rubber lip at one end adapted to snap around one axialextremity of said wear sleeve and a metal member bonded to andsupporting one end of said elastomeric portion and having a radialportion lying between said Y radial flange of said seal assembly andsaid outstepped inner radial portion of said outer case, so as to locksaid mounting and locking ring to said cases so that the entire assemblyis unitized upon installation of said wear sleeve. 6. In a plural-partannular unitized seal assembly for preventing lubricant loss between ashaft and a bore, the combination of:

an outer annular case having a cylindrical portion for snugly engagingVsaid bore and a radial flange at one end of said cylindrical portion,said flange having an axially outstepped inner radial portion; an innerannular case within said outer case having an annular radial flange atone end thereof in opposed relation to said flange of said outer case;an annular resilient lip element supported by said inner case; a metalwear sleeve in rotary sealing engagement with said lip element; and amounting sleeve having a cylindrical elastomeric portion extending thelength of said wear sleeve and in engagement therewith and a rigidradially outwardly extending member secured to one end of saidelastomeric portion and trapped between the two said radial flanges ofsaid cases. 7. The device according to claim 6 wherein said radialvlyoutwardly extending member has a radially extending elastomeric facingbonded thereto.

8. A unitized shaft seal for preventing lubricant loss from between tworelatively rotating members while also protecting them from the ingressof foreign matter between them, including in combination: two annularmetal members, both L-shaped in cross-section to provide a cylindricalportionand a radial flange, the cylindrical portion of the inner of saidmetal members being much shorter than that of the outer said metalmember, said metal members being nested together with the outer surfaceof the cylindrical portion of one facing the inner surface of thecylindrical portion of the other, their radial flanges being at oppositeends; an elastomeric member secured to the inner of said annular membersand in contact with most of the inner surface of the cylindrical portionof the outer said metal member and adapted to snugly engage the innersaid rotating member to secure said metal members against relative axialand rotative movement; a shaft-sealing assembly adapted to engage theother said rotating member and having a sealing lip in rotary sealingengagement with the surface of said cylindrical portion of the outersaid nested metal member; and means unitizing said shaft sealingassembly to said two metal members.

9. In a plural-part annular unitized seal assembly for preventinglubricant loss between two relatively rotatable machine members; anouter annular case adapted to have a stationary leak-tight fit with onesaid machine member and having an annular radial flange surrounding thesecond said machine member and stepped to provide an axially outsteppedinner radial portion of said flange; an inner annular case within saidouter case having an annular radial flange at one side thereof inopposed relation to said radial flange of said outer case; a gasketbetween said radial flanges; an annular resilient lip element secured tosaid'inner case; and an annular two-ply wear sleeve assembly comprisingtwo metal rings together, one providing a radially outer wear sleeve,and the other having secured to one end a radially inner mounting sleevehaving a cylindrical elastomeric portion extending most of the length ofsaid wear sleeve and a rubber lip at the other end adapted to snaparound said wear sleeve.

10. The device according to claim 9 wherein said other metal ring has aradial flange in opposed relation to said radial flanges of said casesand between said cases.

11. The device according to claim 9 wherein said radial flange of saidring has an elastomeric facing bonded thereto and integral with saidmounting sleeve.

12. A unitized shaft seal for preventing lubricant loss from between tworelatively rotating members while also protecting them from the ingressof foreign matter between them, including in combination: two annularmetal members, both L-shaped in cross section to prow'de a cylindricalportion and a radial flange, said metal members being nested togetherwith the outer surface of the cylindrical portion of one facing theinner surface of the cylindrical portion of the other, their radialflanges being at opposite ends; an elastomeric member secured to theinner of said annular members and in contact with most of the innersurface of the cylindrical portion of the outer said metal member andadapted to snugly engage the outer said rotating member to secure saidmetal members against relative axial and rotative movement; ashaftsealing assembly adapted to engage the other said rotating memberand comprising a third metal member and a sealing lip supported by saidthird metal member in rotary sealing engagement with the surface of saidcylindrical portion of the outer said nested metal member which lies onthe opposite radial side from said elastomeric member, said lip and atleast a portion of the third metal member lying axially between saidradial flanges, said third metal member also providing a cylindricalportion, spaced radially from said nested members; and means unitizingsaid shaft sealing assembly to said inner metal member.

13. Ak radial shaft seal including in combination:

a shaft seal assembly having a metal case member and a resilientoil-sealing member having a sealing lip,

a wear sleeve having an axial cylindrical portion engaged by said lip;and

a wear-sleeve-supporting member comprising a reinforcing metal memberhaving a radial flange and an elastomeric body bonded to said metalmember and having an elongated axially extending generally cylindricalportion engaging the cylindrical portion of said wear sleeve, and

an enlarged lip portion on its outer peripheral end edge locking saidwear sleeve to said wear-sleeve-supporting member and said sealassembly.

14. A radial shaft seal including in combination:

a shaft seal assembly having a metal case member with a radial flangeand a resilient sealing lip,

a wear sleeve having an axial cylindrical portion engaged by the lip,and

a wear-sleeve-supporting member comprising a reinforcing metal memberwith a radial flange and an elastomeric body bonded to said metal memberand having an elongated axial portion terminating in an outwardlyextending locking lip and lining the periphery of said supportingmember, said wear sleeve being supported by said elongated axial portionand locked in by the locking lip.

l5. A unitized radial shaft seal including in combination:

a shaft seal assembly having a metal case member and a resilientoil-sealing member having a sealing lip,

a wear sleeve having an axial cylindrical portion engaged by said lipand a radially outwardly extending oil llinging portion,`and

a wear-sleeve-supporting member comprising a reinforcing metal memberhaving a flange and a short axial end portion and an elastomeric bodybonded to said metal member and having an elongated axially extendinggenerally cylindrical portion with an enlarged lip portion on its outerperipheral end edge, its outer periphery engaging the cylindricalportion of said wear sleeve with the lip portion beyond and against thesaid cylindrical portion,

said lip portion locking said wear sleeve to said wearsleeve-supportingmember and said seal assembly being retained between the radial flangeof said wearsleeve-supporting member and the radially outwardlyextending oil llinging portion of said wear sleeve.

16. A unitized radial shaft seal including in combination:

a shaft seal assembly having a metal case member with a radial flangeand a resilient sealing lip,

a wear sleeve having an axial cylindrical portion engaged by the lip anda radially outwardly extending oil ilinging portion, and

a wear sleeve supporting member comprising a reinforcing rnetal memberwith a radial flange and an axial portion and an elastomeric body bondedto said metal member and having an elongated axial portion terminatingin an outwardly extending locking lip and lining the periphery of saidaxial portion of said metal member, said elongated axial portionsupporting said wear sleeve with the locking lip holding theoil-flinging portion of the wear sleeve.

17. A unitized radial shaft seal including in combination:

a shaft seal assembly having a metal case with a radial flange and asealing lip supported by said case,

a wear sleeve having an axial cylindrical portion engaged by the lip anda radially outwardly extending oil flinging portion,

an outer case holding said seal assembly and having an inner radialportion spaced away from said radial flange, and

a wear-sleeve-Supporting member with a rigid reinforcing member having aradial flange and a short axial end portion and an elastomeric bodybonded to said metal member and having an elongated generallycylindrical portion fitting against the cylindrical portion of said wearsleeve with an enlarged generally radial lip projecting out from itsouter peripheral end edge and locking against the radially outwardlyextending oil llinging portion.

18. A unitized radial shaft seal including in combination:

a shaft seal assembly having a metal case member with an axial flange, aradial flange, and an anchor portion, and an elastomeric member securedto said anchor portion and having a sealing lip,

a wear sleeve having an axial cylindrical portion engaged by the lip anda radially outwardly extending oil llinging portion at the oppositeaxial end from said radial flange,

an outer case holding said seal assembly and having a cylindrical flangeagainst which the axial flange of said metal case member fits, saidcylindrical flange having an inturned end portion clamping said axialflange, an outer radial portion against which a portion of the radialange of the metal case member is forced by said inturned end portion,and an offset inner radial portion joined to said outer radial portionby an offset-axial portion,

a gasket between said radial flange and said outer radial portion,

a wear-sleeve-supporting member comprising a metal member having aradial ange and a short radially inner axial end portion, and

an elastomeric body bonded to said metal member and covering its innerperiphery and extending axially well beyond said short axial end portionto provide a generally cylindrical portion with a radially outwardlyextending locking lip, said cylindrical portion lying snugly against theinner periphery of said Wear sleeve with said locking lip engaging andholding said radially outwardly extending oil inging portion of the wearsleeve,

said elastomeric body also covering the surface of said radial flange ofsaid metal member that lies on the opposite side of said metal memberfrom said locking lip,

said radial lange of said metal member lying between said radial flangeof said case member and said inner radial portion of said outer case.

References Cited in the file of this patent UNITED STATES PATENTS

1. AN ANNULAR UNITIZED ASSEMBLY FOR PREVENTING LUBRICANT LOSS BETWEENTWO RELATIVELY ROTATABLE MACHINE MEMBERS COMPRISING: A SEAL ASSEMBLYHAVING AN ANNULAR CASE WITH A RADIAL FLANGE AND AN ANNULAR RESILIENTMEMBER HAVING A SEALING LIP; AN OUTER ANNULAR CASE LOCKED TO SAID SEALASSEMBLY AND ADAPTED TO HAVE A STATIONARY LEAK-TIGHT FIT WITH ONE SAIDMACHINE MEMBER AND HAVING AN ANNULAR RADIAL FLANGE SURROUNDING THESECOND SAID MACHINE MEMBER AND STEPPED TO PROVIDE A RADIALLY OUTERPORTION ABUT TING THE RADIAL FLANGE OF SAID SEAL ASSEMBLY CASE AND ATAXIALLY OUTSTEPPED RADIALLY INNER PORTION SPACED AWAY THEREFROM; A METALRING PROVIDING A GENERALLY CYLINDRICAL WEAR SLEEVE ENGAGED BY SAIDSEALING LIP; AND A MOUNTING AND LOCKING RING HAVING A CYLINDRICALELALSTOMERIC PORTION HAVING A STATIONARY LEAK-TIGHT FIT AGAINST SAIDSECOND SAID MACHINE MEMBER AND FITTING FLUSH AGAINST THE INNER PERIPHERYOF SAID WEAR SLEEVE FOR MOST OF ITS AXIAL EXTENT AND HAVING A RUBBER LIPAT ONE END ADAPTED TO ENGAGE ONE AXIAL EXTREMITY OF SAID WEAR SLEEVE ANDA METAL MEMBER BONDED TO AND SUPPORTING THE OTHER END OF SAIDELASTOMERIC PORTION AND HAVING A RADIAL PORTION LYING BETWEEN SAIDRADIAL FLANGE OF SAID SEAL ASSEMBLY AND SAID OUTSTEPPED IINNER RADIALPORTION OF SAID OUTER CASE SO AS TO LOCK SAID MOUNTING AND LOCKING RINGTO SAID CASES.